Bridge scoring

Duplicate scoring is focused on tournament competition and has many variations that compare and rank the relative performance of partnerships and teams playing the same deals as their competitors.

This is the list of the scoring elements: Contract points are awarded for each odd trick bid and made.

Their values depend on the suit (or notrump) and whether the contract is doubled or redoubled; they are not affected by vulnerability.

Tricks won beyond that necessary to fulfill the contract are referred to as overtricks and their scoring points are accounted for separately because their values are dependent upon declarer's vulnerability.

Honors may be declared and scored at any time after the auction but for strategic reasons it is best to do so at the conclusion of play so as not to give the opponents information about the lay of the cards.

Furthermore, the part score of 70 by North-South is no longer available for accumulation towards a game by them; the 70 points are said to be "cut off" as signified by the drawing of the horizontal line.

Having won a game, East-West are vulnerable for all subsequent deals of the rubber meaning that they are now eligible for a larger rubber bonus if they win a second game before their opponents win one and they are susceptible to increased penalties if they are defeated in a contract.

Deal 6: East bids and makes 6♦ - a small slam holding all five top honors.

Since there are only two teams involved, the only possible results are 1 (won), ½ (tied), and 0 (lost) points per board.

[2][3] The purpose of the IMP table, which has sublinear dependency on differences, is to reduce results occurring from large swings.

In some events (for example, Swiss Teams), a further normalization to reduce the effect of large swings is applied to the International Match Point scores.

A specific number of Victory Points, either 20 or 30, are divided between the two teams in accordance with the following scales: In the 1932 Laws of Contract Bridge, notrump tricks bid and made, and undoubled notrump tricks made but not bid, score 30, 40, 30, 40, 30, 40, 30.

A change to the scoring of the fourth and subsequent non-vulnerable undertricks, from 200 each to 300 each, was made in 1987 after a hand in the finals of the 1981 Bermuda Bowl.

Munir Attaullah and Jan-e-Alam Fazli, playing for Pakistan, reached a vulnerable 7♥ contract, which would have scored them 2210.

But their non-vulnerable opponent Jeff Meckstroth, playing for USA, calculated that down 11 would cost only 2100 points and thinking he might do better than that,[8] sacrificed in 7♠ on a weak hand with five spades to the jack; this was doubled and went down nine for a score of -1700.

This was changed to 100, so that playing 5 of a minor, redoubled, making an overtrick, is always worth more than an undoubled small slam.

International Match Point scoring was first introduced at the 1938 European Championships in Oslo.

[11] The difference in total points scored by each team is converted to International Match Points (IMPs) using a standard table[2][12] which has sublinear dependencies on differences to reduce the effect of such large swings.

A revised table was adopted for the 1948 European Championships in Copenhagen with a maximum of 15 points.

North American players were first introduced to this scoring method at the 1951 Bermuda Bowl match in Naples, Italy.